/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.mpp.transformation.dag.adapter;

import org.apache.iotdb.commons.udf.utils.UDFDataTypeTransformer;
import org.apache.iotdb.db.mpp.transformation.datastructure.row.ElasticSerializableRowRecordList;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.udf.api.access.Row;
import org.apache.iotdb.udf.api.access.RowIterator;
import org.apache.iotdb.udf.api.access.RowWindow;
import org.apache.iotdb.udf.api.type.Type;

import java.io.IOException;

public class ElasticSerializableRowRecordListBackedMultiColumnWindow implements RowWindow {

    private final ElasticSerializableRowRecordList rowRecordList;
    private final TSDataType[] dataTypes;

    private int beginIndex;
    private int endIndex;
    private int size;

    private long startTime;
    private long endTime;

    private final ElasticSerializableRowRecordListBackedMultiColumnRow row;
    private ElasticSerializableRowRecordListBackedMultiColumnWindowIterator rowIterator;

    public ElasticSerializableRowRecordListBackedMultiColumnWindow(
            ElasticSerializableRowRecordList rowRecordList) {
        this.rowRecordList = rowRecordList;
        this.dataTypes = rowRecordList.getDataTypes();

        beginIndex = 0;
        endIndex = 0;
        size = 0;

        row = new ElasticSerializableRowRecordListBackedMultiColumnRow(dataTypes);
    }

    @Override
    public int windowSize() {
        return size;
    }

    @Override
    public Row getRow(int rowIndex) throws IOException {
        if (this.size == 0) {
            throw new IndexOutOfBoundsException("Size is 0");
        }
        return row.setRowRecord(rowRecordList.getRowRecord(beginIndex + rowIndex));
    }

    @Override
    public Type getDataType(int columnIndex) {
        return UDFDataTypeTransformer.transformToUDFDataType(dataTypes[columnIndex]);
    }

    @Override
    public RowIterator getRowIterator() {
        if (this.size == 0) {
            return new EmptyRowIterator();
        }
        if (rowIterator == null) {
            rowIterator =
                    new ElasticSerializableRowRecordListBackedMultiColumnWindowIterator(
                            rowRecordList, beginIndex, endIndex);
        }

        rowIterator.reset();
        return rowIterator;
    }

    @Override
    public long windowStartTime() {
        return startTime;
    }

    @Override
    public long windowEndTime() {
        return endTime;
    }

    public void setEmptyWindow(long startTime, long endTime) {
        this.startTime = startTime;
        this.endTime = endTime;
        this.size = 0;
    }

    public void seek(int beginIndex, int endIndex, long startTime, long endTime) {
        this.beginIndex = beginIndex;
        this.endIndex = endIndex;
        size = endIndex - beginIndex;

        this.startTime = startTime;
        this.endTime = endTime;

        rowIterator = null;
    }
}
